The design of semiconductor manufacturing equipment is driven by the trend toward higher density integrated circuits. In an optical projection system decrease in feature size theoretically is limited only by the capability of the system to function at short wavelengths, i.e., the further into the U.V. region of the spectrum the projection light source extends, the smaller will be the feature size. In practice, however, feature size is limited by the resolution capabilities of the optical system, i.e., the capability of the optical system to transmit the object as an image substantially free of aberrations introduced by the optics. The problem of maintaining high resolution, i.e., an optical system substantially free of aberrations is exacerbated further where the projection system is designed to include the added advantage of reduction, i.e., reduction of the size of the object when it is imaged.